When creating an EC2 instance, you'd already have a default root volume.

Mounting an EBS volume to EC2 is like adding a hard disk to your laptop. You'll get an additional block storage on top of the default one.

Follow these steps: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-using-volumes.html.

What you will do is: 1. Create a new block volume. 2. Create a new directory (path) in EC2. 3. Mount that block volume onto that path.

If the instance is rebooted, the volume will not automatically attach. So continue on with automatically mounting it.

4. Configure to automatically attach after reboot.
5. Reboot the instance to see if it does reattach automatically.

Always run sudo lsblk to have an overview of the volumes and mount directories.